WO2013170789A1

WO2013170789A1 - Data-forwarding method, apparatus and communications system

Info

Publication number: WO2013170789A1
Application number: PCT/CN2013/075840
Authority: WO
Inventors: 戴明增; 郭轶; 曾清海; 张宏平
Original assignee: 华为技术有限公司
Priority date: 2012-05-18
Filing date: 2013-05-17
Publication date: 2013-11-21
Also published as: CN103428788B; US20200015143A1; US9686730B2; KR20150008480A; KR101706614B1; CN106332198B; EP3297330B1; CN106332198A; EP2846583A1; US10425876B2; KR102029083B1; KR20170017016A; KR101917339B1; KR20180122751A; EP2846583A4; EP3297330A1; JP2015516784A; CN103428788A; EP2846583B1; US20150071250A1

Abstract

The embodiments of the present invention relate to the technical field of communications and provide a data-forwarding method, apparatus and communications system, which realize the veracity and continuity of data transmission during inter-station cell carrier aggregation. The method comprises: a master base station (BS) sending a first message to a subordinate BS, the first message for use to indicate the subordinate BS to perform handover, and the first message including the identification of a target BS; the master BS verifying that the subordinate BS forwards data to the target BS; and the master BS sending a second message to a user equipment (UE), the second message for use to indicate the UE to obtain the data from the target BS. The embodiments of the present invention are used in forwarding data.

Description

Method, device and communication system for data forwarding The present application claims to be submitted to the Chinese Patent Office on May 18, 2012, the application number is CN 201210155172.7, and the invention name is "a method, device and communication system for data forwarding". Priority of the patent application, the entire contents of which is incorporated herein by reference. Technical field

The present invention relates to the field of communications, and in particular, to a data forwarding method, device, and communication system.

Background technique

With the development of mobile communication systems, the quality of services provided by communication systems is also increasing. In order to maintain the long-term competitive advantage of 3GPP (the 3rd Generation Partnership), LTE-A (LTE-advanced) is a further evolution of LTE (long term evolut ion) technology. Standard development work for the subsequent evolution of the Long Term Evolution System is underway. In order to further improve the spectrum efficiency of the communication system and the data throughput of the user, a carrier aggregation (CA) technology is introduced into LTE-A. Carrier aggregation means that user equipment (UE) can use multiple component carriers (CC, component carr ier) for uplink and downlink communication, thus enabling high-speed data transmission.

The carrier aggregation of the LTE system can be roughly divided into carrier aggregation of cells in the base station and carrier aggregation of cells between the base stations. Carrier aggregation of cells within the base station is relatively easy to implement since it is controlled by only one base station. The carrier aggregation of the inter-base station cell can be further divided into carrier aggregation of cells between macro base stations and carrier aggregation of cells between macro base stations and home base stations. The carrier aggregation of the cell between the macro base stations can improve the data throughput of the users in the edge zone of the base station, thereby improving the user experience. In addition to improving the data throughput of the user, the carrier aggregation of the cell between the macro base station and the home base station can also be used to offload the macro network. The system load can also reduce the occurrence of handovers compared to a pure home base station network.

When carrying out high-speed data transmission using carrier aggregation of cells between base stations, when carrying data bases When the station switches, the existing carrier aggregation data transmission method is difficult to achieve the accuracy and continuity of the data transmission, which will result in the loss of data when the handover occurs, thereby reducing the user's sense of use.

The invention provides a data forwarding method, device and communication system, which can realize the accuracy and continuity of data transmission during cell carrier aggregation between base stations.

In order to achieve the above object, embodiments of the present invention use the following technical solutions:

An aspect of the present invention provides a data forwarding method, involving a primary base station, including: a primary base station sends a first message to a secondary base station, where the first message is used to indicate that the secondary base station performs handover, and the first message includes a target. Base station identification;

The primary base station confirms that the secondary base station forwards data to the target base station; and

The primary base station sends a second message to the user equipment, where the second message is used to instruct the user equipment to acquire the data from the target base station.

In another aspect, the present invention provides a data forwarding method, involving a secondary base station, including: a secondary base station receiving a first message sent by a primary base station, where the first message is used to instruct the secondary base station to perform handover, the first message Including the target base station identifier;

Receiving, by the secondary base station, a data forwarding acknowledgement message sent by the target base station, where the data forwarding acknowledgement message is used to confirm that the secondary base station performs data forwarding to the target base station;

The secondary base station sends a second message to the primary base station, where the second message is used by the primary base station to instruct the user equipment to acquire the data from the target base station.

Another aspect of the present invention provides a base station, including:

a transmitter, configured to send a first message to the secondary base station, where the first message is used to indicate that the secondary base station performs handover, and the first message includes a target base station identifier;

a processor, configured to: confirm that the secondary base station forwards data to the target base station; and the transmitter is further configured to send a second message to the user equipment, where the second message is used to indicate that the user equipment is from the target The base station acquires the data. Another aspect of the present invention provides a base station, including:

a receiver, configured to receive a first message sent by the primary base station, where the first message is used to indicate that the base station performs handover, and the first message includes a target base station identifier;

The receiver is further configured to receive a data forwarding acknowledgement message sent by the target base station, where the data forwarding acknowledgement message is used to confirm that the base station performs data forwarding to the target base station, and a transmitter is configured to send to the primary The base station forwards the second message, where the second message is used by the primary base station to instruct the user equipment to acquire the data from the target base station.

In still another aspect of the present invention, a communication system is provided, comprising the base station as described above. The method, device, and system for data forwarding provided by the embodiment of the present invention, the primary base station sends a first message carrying the identifier of the target base station to the secondary base station, to indicate that the secondary base station performs handover; and the primary base station confirms that the secondary base station forwards to the target base station. Data, and sending a second message to the user equipment to inform the user equipment to acquire data from the target base station. Using such a data forwarding method, seamless handover between base stations can be performed in the case of cell carrier aggregation between base stations, thereby avoiding data loss when handover occurs in the case of cell carrier aggregation between base stations, thereby realizing inter-base station handover. Accurate continuous transmission of data during cell carrier aggregation reduces the delay of data transmission.

DRAWINGS

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the embodiments or the description of the prior art will be briefly described below. Obviously, the drawings in the following description are only It is a certain embodiment of the present invention, and other drawings can be obtained from those skilled in the art without any creative work.

1 is a schematic flowchart of a data forwarding method according to an embodiment of the present invention; FIG. 2 is a schematic flowchart of a data forwarding method according to an embodiment of the present invention; FIG. 3 is another data forwarding method according to an embodiment of the present invention; FIG. 4 is a schematic flowchart of another data forwarding method according to an embodiment of the present invention; FIG. 5 is a schematic diagram of a signaling flow of a data forwarding method according to an embodiment of the present invention; FIG. 6 is a schematic diagram of an internal operation process of a user equipment in a data forwarding method according to an embodiment of the present disclosure;

FIG. 7 is a schematic diagram of a signaling flow of another data forwarding method according to an embodiment of the present invention; FIG. 8 is a schematic diagram of a signaling flow of another data forwarding method according to an embodiment of the present invention; FIG. FIG. 10 is a schematic diagram of a signaling flow of another data forwarding method according to an embodiment of the present invention; FIG. 11 is a schematic structural diagram of a base station according to an embodiment of the present invention;

FIG. 12 is a schematic structural diagram of another base station according to an embodiment of the present disclosure;

FIG. 13 is a schematic structural diagram of another base station according to an embodiment of the present disclosure;

FIG. 14 is a schematic structural diagram of another base station according to an embodiment of the present disclosure;

FIG. 15 is a schematic structural diagram of another base station according to an embodiment of the present disclosure;

FIG. 16 is a schematic structural diagram of a user equipment according to an embodiment of the present invention.

detailed description

The technical solutions in the embodiments of the present invention are clearly and completely described in the following with reference to the accompanying drawings in the embodiments of the present invention. It is obvious that the described embodiments are only a part of the embodiments of the present invention, but not all of the embodiments. All other embodiments obtained by a person of ordinary skill in the art based on the embodiments of the present invention without creative efforts are within the scope of the present invention.

Various aspects are described herein in connection with a terminal and/or a base station.

A terminal, a device that provides voice and/or data connectivity to a user, including a wireless terminal or a wired terminal. The wireless terminal can be a handheld device with wireless connectivity, or other processing device connected to the wireless modem, and a mobile terminal that communicates with one or more core networks via a wireless access network. For example, the wireless terminal can be a mobile phone (or "cellular" phone) and a computer with a mobile terminal. As another example, the wireless terminal can also be a portable, pocket, handheld, computer built-in or in-vehicle mobile device. For another example, the wireless terminal can be a mobile station (in English: mobi s ta t ion ), an access point (in English: acces s point ), or user equipment (English) The text is: user equi pment, referred to as UE).

A base station may refer to a device in an access network that communicates with a wireless terminal over one or more cells over an air interface. For example, the base station may be a base station in GSM or CDMA (base transceiver s ta t ion, BTS for short), or a base station in WCDMA (in English: NodeB), or an evolved base station in LTE. (English: evolut iona l Node B, referred to as eNB or e-NodeB), or a base station in a subsequent evolved network, which is not limited by the present invention.

In the embodiments of the present invention, the primary base station is a control base station for controlling a data forwarding process, and the secondary base station is a base station used to share part of data resources required for user equipment access in order to improve user data traffic or reduce interference. The target base station is a base station used to share data resources required for user equipment access after the handover occurs. The mobility management entity (MME) is the control node of the LTE access network in the 3GPP protocol, and is mainly responsible for positioning, paging, and relaying of user equipment in idle mode.

The data forwarding method provided by the embodiment of the present invention relates to a primary base station. As shown in FIG. 1 , the method includes: S10: The primary base station sends a first message to the secondary base station, where the first message is used to indicate that the secondary base station performs handover, the first message. Includes the target base station identity.

5102. The primary base station confirms that the secondary base station forwards data to the target base station.

The primary base station sends a second message to the user equipment, where the second message is used to indicate that the user equipment acquires the data from the target base station.

It should be noted that, in the data forwarding method provided by the embodiment of the present invention, the primary base station and the target base station may be the same base station.

This embodiment can implement the accuracy and continuity of data transmission when two or more base stations simultaneously transmit data to one user terminal, such as cell carrier aggregation between base stations.

上述 Using the above data forwarding method, seamless handover between base stations can be performed in the case of cell carrier aggregation between base stations, thereby avoiding data loss when handover occurs in the case of cell carrier aggregation between base stations, thereby realizing inter-base station cell carrier Accurate continuous transmission of data during aggregation, reduced The delay of data transmission.

On the other hand, the data forwarding method provided by the embodiment of the present invention relates to a secondary base station, as shown in FIG. 1 , including:

The S20 receives the first message sent by the primary base station, where the first message is used to indicate that the secondary base station performs the handover, and the first message includes the target base station identifier.

S202. The secondary base station receives a data forwarding acknowledgement message sent by the target base station, where the data forwarding acknowledgement message is used to confirm that the secondary base station performs data forwarding to the target base station.

S203. The secondary base station sends a second message to the primary base station, where the second message is used by the primary base station to instruct the user equipment to obtain the data from the target base station.

上述 Using the above data forwarding method, seamless handover between base stations can be performed in the case of cell carrier aggregation between base stations, thereby avoiding data loss when handover occurs in the case of cell carrier aggregation between base stations, thereby realizing inter-base station cell carrier Accurate continuous transmission of data during aggregation reduces the delay of data transmission.

On the other hand, the data forwarding method provided by the embodiment of the present invention relates to a target base station, as shown in FIG. 3, including:

S 301. The target base station receives the sequence number SN (sequence number) state transition information of the data packet sent by the primary base station or the secondary base station.

5302. The target base station sends a path switch request to the mobility management entity MME.

S303. The target base station receives the path switch confirmation information sent by the MME, and completes data forwarding.上述 Using the above data forwarding method, seamless handover between base stations can be performed in the case of cell carrier aggregation between base stations, thereby avoiding data loss when handover occurs in the case of cell carrier aggregation between base stations, thereby realizing inter-base station cell carrier Accurate continuous transmission of data during aggregation reduces the delay of data transmission.

On the other hand, the data forwarding method provided by the embodiment of the present invention further relates to the user equipment, as shown in FIG. 4, including:

S401. The user equipment receives a second message sent by the primary base station, where the second message is used to indicate the The user equipment acquires data from the target base station.

S402. The user equipment establishes, according to the second message, a protocol entity corresponding to the target base station protocol entity on the user equipment side.

S403. The user equipment forwards the cached data in the secondary base station protocol entity to the target base station protocol entity.

As shown in FIG. 5, the embodiment of the present invention further provides a specific description of the foregoing data forwarding method embodiment, including:

The S50 primary base station sends a first message to the secondary base station, where the first message is used to indicate that the secondary base station performs handover, and the first message includes a target base station identifier.

For example, in any of the following cases, the primary base station determines that the secondary base station needs to perform handover, and the primary base station sends a first message to the secondary base station:

When the primary base station confirms that the signal quality of the secondary base station is lower than a preset threshold, the primary base station sends a first message to the secondary base station. For example, when the primary base station determines that the secondary base station needs to perform handover according to the RSRP (reference s igna l rece iving power) of the secondary base station reported by the user equipment, the primary base station may determine that the secondary base station needs to perform handover, and the primary base station The secondary base station sends the first message.

Or, when the primary base station receives the radio access bearer handover request sent by the secondary base station, the primary base station sends a first message to the secondary base station. For example, when the secondary base station detects that its own load is too heavy, the secondary base station may actively send a handover request to the primary base station, and the primary base station determines that the secondary base station needs to perform handover, and the primary base station sends a first message to the secondary base station.

Or, when the primary base station confirms that the wireless link connection between the user equipment and the secondary base station fails, the primary base station sends a first message to the secondary base station. For example, when the primary base station receives the assistance reported by the user equipment The base station radio link failure indication, and when receiving the radio link failure indication sent by the secondary base station, the primary base station may determine that the secondary base station needs to perform handover, and the primary base station sends the first message to the secondary base station.

Further, the sending, by the primary base station, the first message to the secondary base station may include:

The primary base station determines that the secondary base station performs a partial radio access handover, and sends a radio access bearer handover message to the secondary base station, where the secondary base station switches the partial radio access bearer to the target base station, and the radio access The bearer handover message includes an identifier of the part of the radio access bearer. The radio access bearer switching message may further include an identifier of the target base station, where the identifier may include the base station.

ID (identity), global base station ID, cell ID, or global cell ID.

Alternatively, the primary base station determines that the secondary base station performs all radio access bearer handover, and sends a secondary base station handover command to the secondary base station, where the secondary base station switches all radio access bearers to the target base station. For example, if the primary base station decides to switch all the radio access bearers on the secondary base station to the target base station, the secondary base station handover command may be used instead of the radio access bearer handover message. When the secondary base station receives the base station handover command, the secondary base station considers all the wireless The access bearers need to be switched.

In the embodiment of the present invention, the target base station and the primary base station may be the same base station.

S502. The secondary base station stops the transmission of uplink and downlink data.

For example, after receiving the first message sent by the primary base station, the secondary base station immediately stops the uplink and downlink data transmission when it determines that it has an uplink and downlink data buffer or has uplink and downlink data that is not authenticated by the user equipment.

S503. The secondary base station sends a data forwarding request message to the primary base station, where the data forwarding request message is used to request data forwarding from the primary base station, where the data forwarding request message includes information indicating that the primary base station performs downlink forwarding, and/or the secondary base station. Uplink General Packet Radio Service Tunneling Protocol GTP endpoint information.

For example, if the secondary base station decides to suggest that the primary base station forward downlink data, it includes a suggested downlink forwarding indication to the primary base station. If the primary base station decides to recommend uplink data forwarding, the uplink GTP endpoint is sent to the primary base station. Optionally, the secondary base station may carry configuration information to the primary base station in the message, so that the primary base station determines whether to continue to use the same configuration, and the configuration information may include the bearer. MAC (medium acces s control, media access control 'J) West parameters or RLC (radio l ink cont rol) configuration parameters. For example, when the MAC configuration parameter of the bearer is unchanged, the primary base station can continue to use the configuration to carry data.

S504: The secondary base station receives a data forwarding acknowledgement message sent by the primary base station, where the data forwarding acknowledgement message is used to confirm that the secondary base station performs data forwarding to the primary base station.

The primary base station confirms that the secondary base station forwards data to the primary base station itself.

For example, after receiving the data forwarding request message, the primary base station determines whether data forwarding is allowed. If the primary base station allows data forwarding, the data forwarding acknowledgement message is sent to the secondary base station, where the message may carry the GTP endpoint information of the primary base station.

S505. The primary base station receives SN state transition information of the data packet sent by the secondary base station.

For example, after receiving the data forwarding acknowledgement message sent by the primary base station, the secondary base station indicates the sequence number list of the bearer forwarding data in the SN state transition information of the data packet, and the list helps the primary base station notify the user equipment in advance that the device does not have to be heavy. The transmitted uplink data packet may help the primary base station determine the downlink packet that needs to be retransmitted through the wireless interface. And the data forwarding GTP tunnel is established according to the GTP endpoint information, and the secondary base station forwards the received out-of-order uplink data and/or the downlink data that has not been confirmed by the user equipment to the primary base station.

S506. The primary base station sends a second message to the user equipment, where the second message is used to indicate that the user equipment acquires the data from the target base station.

Specifically, the primary base station sends a second message to the user equipment, where the second message may be a radio resource control, and the second message may be included in the RRC message. The radio access bearer is instructed to switch from the secondary base station to the primary base station.

S 507. The primary base station sends a path switch request to the mobility management entity.

In the message, the radio access bearer handover indication may be added, and the indication is forwarded to the serving gateway S-GW (servic ing ga teway). After receiving the indication, the fixed E and the S-GW only perform path switching on the corresponding radio access bearer, and other radio access bearers are not affected. For example, other radio access bearers do not release the S1 of the MME and the primary base station. connection. S508. The primary base station receives the path switch confirmation information sent by the solid E, and completes data forwarding.

S509. The primary base station sends a handover success message to the secondary base station, so that the secondary base station releases the carried data.

For example, after the secondary base station receives the handover success message, the RLC, MAC, or PDCP (packet data convergence protocol) is released.

In this embodiment, after the user equipment receives the second message, the specific internal operations may be as shown in FIG. 6.

S601. The user equipment receives a second message sent by the primary base station, where the second message is used to indicate that the user equipment acquires data from the target base station.

The RRC (Radio Resource Control) layer of the user equipment receives the second message sent by the primary base station, where the second message may be a radio resource reconfiguration message, and the RRC layer of the user equipment retransmits the message according to the radio resource. Configure a protocol entity for carrying radio resources.

S602. The user equipment establishes, according to the second message, a protocol entity corresponding to the target base station protocol entity on the user equipment side.

S 603. The user equipment forwards the cached data in the secondary base station protocol entity to the target base station protocol entity.

It should be noted that the protocol entity may be at least one of a PDCP protocol entity, an RLC (Radio Link Control Protocol) protocol entity, or a MAC (Medium Acces s Control) protocol entity.

Optionally, the internal operations of the user equipment may further include:

S604. The user equipment sends the RRC connection reconfiguration complete information to the primary base station.

上述 Using the above data forwarding method, seamless handover between base stations can be performed in the case of cell carrier aggregation between base stations, thereby avoiding data loss when handover occurs in the case of cell carrier aggregation between base stations, thereby realizing inter-base station cell carrier Accurate continuous transmission of data during aggregation reduces the delay of data transmission. As shown in FIG. 7, the embodiment further provides a specific description of the foregoing embodiment, including: S70: The primary base station sends a first message to the secondary base station, where the first message is used to indicate that the secondary base station performs handover, and the first message includes a target. Base station identification.

5702. The secondary base station stops the transmission of uplink and downlink data.

The above steps can be referred to the foregoing embodiment, and are not mentioned here.

S703, the secondary base station sends a data forwarding request message to the target base station, where the data forwarding request message is used to request data forwarding from the target base station, where the data forwarding request message includes information indicating that the target base station performs downlink forwarding, and/or the secondary base station Uplink General Packet Radio Service Tunneling Protocol GTP Endpoint Information.

Different from the foregoing embodiments, in the embodiment of the present invention, the target base station and the primary base station may not use one base station.

S704. The secondary base station receives a data forwarding acknowledgement message sent by the target base station, where the data forwarding acknowledgement message is used to confirm that the secondary base station performs data forwarding to the target base station.

For example, after receiving the data forwarding request message, the target base station determines whether to allow data forwarding. If the target base station allows data forwarding, the data forwarding acknowledgement message is sent to the secondary base station, where the message may carry the GTP endpoint information of the target base station.

S705: The target base station receives the SN state transition information of the data packet sent by the secondary base station.

For example, after receiving the data forwarding acknowledgement message sent by the target base station, the secondary base station indicates the sequence number list of the bearer forwarding data in the SN state transition information of the data packet, and the list helps the target base station notify the user equipment in advance that the device does not have to be heavy. The transmitted uplink data packet may help the target base station determine the downlink packet that needs to be retransmitted through the wireless interface. And the data forwarding GTP tunnel is established according to the GTP endpoint information, and the secondary base station forwards the received out-of-order uplink data and/or the downlink data that has not been acknowledged by the user equipment to the target base station.

S706. The primary base station sends a second message to the user equipment, where the second message is used to indicate that the user equipment acquires the data from the target base station. The second message may be an RRC connection reconfiguration message, where the message may carry a radio access bearer handover indication. After the user equipment receives the radio access bearer switching indication, the specific internal operations may be as shown in FIG. 6 above, and details are not described herein.

S707. The target base station sends a path switch request to the mobility management entity MME.

In the message, the radio access bearer handover indication may be added, and the indication is forwarded to the signaling gateway S-GW. After receiving the indication, the MME and the S-GW only perform path switching on the corresponding radio access bearer, and other radio access bearers are not affected. For example, other radio access bearers do not release the solid E and the primary base station S1. connection.

S708: The target base station receives the path switch confirmation information sent by the MME, and completes data forwarding. S709. The target base station sends a handover success message to the secondary base station, so that the secondary base station releases the carried data.

For example, after the secondary base station receives the handover success message, the RLC, MAC or PDCP configuration is released.

The data forwarding method provided by the embodiment of the present invention is as shown in FIG. 8. In this embodiment, the primary base station changes (the primary base station switches to the target base station), and the primary base station requests the secondary base station to change, and the anchor point of the data forwarding is in the main Base station, the method includes:

The primary base station determines to handover to the target base station;

The primary base station sends a request message to the secondary base station, where the request message is used to request the secondary base station to perform data forwarding;

Receiving, by the primary base station, an acknowledgment message sent by the secondary base station, where the acknowledgment message includes at least one of the following information: information indicating that the primary base station performs downlink data forwarding, and uplink common packet radio service tunneling protocol GTP endpoint information of the secondary base station to perform Uplink data forwarding The method can further include:

When the S80 primary base station determines that the secondary base station needs to be switched or deactivated, it sends a data query command to the secondary base station. Factors affecting the handover decision are load, traffic, and signal quality.

For example, if the primary base station decides to switch or deactivate the secondary base station, it sends a data query command to the secondary base station, and the data query command may include an indirect forwarding indication.

When the secondary base station determines that the secondary base station needs to be deactivated according to the data query command, the secondary base station sends a data forwarding acknowledgement message to the primary base station, where the data forwarding acknowledgement message is used to request data forwarding from the primary base station, including indicating that the primary base station performs downlink forwarding. Information and/or uplink general packet radio service tunneling protocol GTP endpoint information of the secondary base station.

For example, after receiving the data forwarding query command, the secondary base station determines whether the uplink and downlink data needs to be forwarded to the target base station, and the judgment basis may be at least one of the following: whether there is uplink and downlink data buffer; whether there is a downlink PDCP that is not confirmed by the UE. Service data unit (servi ce da ta un it, SDU for short); whether there are uplink PDCP SDUs that are not correctly ordered. If the secondary base station decides to recommend forwarding downlink data, it includes a suggested downlink forwarding indication to the primary base station. If the secondary base station decides to recommend uplink data forwarding, the uplink GTP endpoint is sent to the primary base station.

S803. The primary base station sends a handover request message to the target base station.

The information received by the primary base station indicating that the primary base station performs downlink forwarding and/or the uplink general packet wireless service tunneling protocol GTP endpoint information of the secondary base station may be brought to the target base station in the handover request message.

Optionally, when sending the handover request message, the primary base station may carry a correspondence between the radio bearer and the secondary base station to the target base station. The corresponding relationship may be in the form of a list or a bitmap, and may include a binding relationship or a mapping relationship between the secondary base station identifier and the radio bearer identifier, to indicate that one or some radio bearers belong to the secondary base station.

S804. The primary base station receives a handover confirmation message sent by the target base station.

The primary base station sends a base station handover command to the secondary base station, instructing the secondary base station to stop the uplink and downlink data transmission and perform data forwarding, so that the secondary base station forwards data to the primary base station. For example, the primary base station receives the handover request acknowledgement message of the target base station, where the message includes the uplink and downlink GTP endpoints forwarded by the data carried by the secondary base station, and sends a base station handover command to the secondary base station, where the command may initiate data forwarding. And the GTP endpoint information of the primary base station. After receiving the indication that the data forwarding is started, the secondary base station may stop transmitting or scheduling uplink and downlink data.

S806. The primary base station sends a second message to the user equipment, where the second message is used to indicate that the user equipment performs radio bearer switching.

For example, the primary base station sends a handover command to the user equipment. The command may be a RRC protocol, and may include an indication that the radio bearer is handed over from the secondary base station to the target base station. After receiving the handover command, the user equipment establishes a new PDCP layer for the radio bearer in the corresponding protocol stack of the target base station protocol stack, and re-orders the PDCP in the corresponding protocol stack of the secondary base station protocol stack. The unordered PDCP SDU is forwarded to the newly established PDCP layer. After the forwarding is completed, the user equipment can release the PDCP layer of the corresponding secondary base station protocol stack.

After the user equipment receives the radio access bearer switching indication, the specific internal operations may be as shown in FIG. 6 above, and are not mentioned here.

S807. The target base station receives the SN state transition information sent by the primary base station. In the embodiment of the present invention, since the primary base station that is the data forwarding target switches to the target base station, the SN state transition information sent by the secondary base station is sent to the primary base station, and then forwarded by the primary base station to the target base station.

In this embodiment, the secondary base station indicates the sequence number of the bearer forwarding data to the primary base station in the SN System Push message, and the list helps the target base station to notify the user terminal in advance that the uplink terminal does not have to retransmit or help. The downlink terminal that needs to be retransmitted through the wireless interface is determined at the target terminal. And the data forwarding GTP tunnel is established according to the GTP endpoint information, and the primary base station forwards the received PDCP SDU of the out-of-order uplink and/or the PDCP SDU that has not been acknowledged by the user terminal to the target base station.

Optionally, the target base station sends the SN status query command of the corresponding bearer to the secondary base station after receiving the handover request message and forwarding the data to the bearer of the secondary base station. Receiving the primary base station After the sent data forwarding acknowledgement message, the secondary base station indicates the sequence number list of the bearer forwarding data to the target base station in the SN System Push message.

In this embodiment, after the primary base station sends the SN state transition information to the target base station, the secondary base station forwards the data to the primary base station, and the primary base station then forwards the data to the target base station to complete the data forwarding process.

S808. The target base station sends a path switch request to the mobility management entity MME.

In the message, the radio access bearer handover indication may be added, and the indication is forwarded to the signaling gateway S-GW. After receiving the indication, the MME and the S-GW only perform path switching on the corresponding radio access bearer, and other radio access bearers are not affected. For example, other radio access bearers do not release the S1 of the MME and the primary base station. connection.

S809: The target base station receives the path switch confirmation information sent by the MME, and completes data forwarding.这样Using such a data forwarding method, it can be applied to the activation/deactivation in the case of cell carrier aggregation between base stations or the forwarding of data when switching occurs, avoiding data when activation/deactivation occurs or switching occurs. Lost, thereby realizing accurate and continuous data transmission during cell carrier aggregation between base stations, and reducing the delay of data transmission.

The data forwarding method provided by the embodiment of the present invention is as shown in FIG. 9. In this embodiment, the primary base station changes (the primary base station switches to the target base station), and the primary base station requests the secondary base station to change, and the data forwarding anchor point is placed. Secondary base station.

This embodiment is identical to the previous embodiment (the anchor point of the data forwarding is in the primary base station), and the difference is in the following two points:

S805': The primary base station sends a data forwarding initiation message to the secondary base station, where the message includes the GTP endpoint information of the target base station. After receiving the message, the secondary base station should stop transmitting or scheduling uplink and downlink data.

S807': the secondary base station indicates the sequence number of the bearer forwarding data to the target base station in the SN ta tus Trans fer message, and the secondary base station establishes a data forwarding GTP tunnel according to the GTP endpoint information, and the secondary base station receives the received outbound PDCP. SDU and/or downlink has not been confirmed by the user equipment The PDCP SDU is forwarded and sent to the target base station.

这样Using such a data forwarding method, it can be applied to the activation/deactivation in the case of cell carrier aggregation between base stations or the forwarding of data when switching occurs, avoiding data when activation/deactivation occurs or switching occurs. Lost, thereby realizing accurate and continuous data transmission during cell carrier aggregation between base stations, and reducing the delay of data transmission.

As shown in FIG. 10, in this embodiment, a data forwarding method is further provided, in which the primary base station performs handover, and the secondary base station remains unchanged. Includes:

The S100 sends a first message to the target base station, where the first message is used to request the handover, and the first message includes the identifier of the secondary base station and the indication that the secondary base station remains unchanged after the handover, that is, only the bearer on the primary base station is switched to The target base station does not switch, and after the handover succeeds, the secondary base station continues to transmit the original bearer under the control of the target base station.

Optionally, the primary base station receives the handover confirmation message sent by the target base station.

51002. The primary base station sends a handover indication to the secondary base station.

For example, after receiving the handover request acknowledgement message, the primary base station sends a handover indication to the secondary base station, notifying that the secondary base station handover is about to start, and instructing the secondary base station to stop transmitting uplink and downlink data.

51003. The primary base station sends a second message to the user equipment.

For example, the handover command may carry an indication that the secondary base station remains unchanged. After receiving the indication, the user equipment maintains the bearer on the secondary base station. The specific internal operation of the user equipment may be as shown in FIG. 6 above. .

For example, the second message may be a handover command, where the handover command may carry an indication that the secondary base station remains unchanged, and after receiving the indication, the user equipment maintains the bearer on the secondary base station.

51004. The target base station receives the SN state transition information sent by the primary base station.

51005. The target base station sends an activation command to the secondary base station.

For example, after receiving the handover complete message, the target base station sends an activation command to the secondary base station. After receiving the command, the secondary base station starts transmitting uplink and downlink data.

S1006. The secondary base station sends a path switch request to the mobility management entity MME. S1007: The secondary base station receives the path switching confirmation information of the solid E transmission, and completes data forwarding.这样Using such a data forwarding method, it can be applied to data forwarding when activation/deactivation occurs in the case of cell carrier aggregation between base stations, thereby avoiding data loss when activation/deactivation occurs, thereby realizing inter-base station cells. Accurate continuous transmission of data during carrier aggregation reduces the delay of data transmission.

The base station 11 provided by the embodiment of the present invention corresponds to the foregoing method embodiment, and is used as the primary base station, and can be used in all the steps in the foregoing method embodiment. The detailed method steps corresponding to the base station 11 have been described in the foregoing method embodiment. More details will be described. As shown in Figure 11, it includes:

The transmitter 111 is configured to send a first message to the secondary base station, where the first message is used to indicate that the secondary base station performs handover, and the first message includes a target base station identifier.

The processor 112 is configured to confirm that the secondary base station forwards data to the target base station.

The transmitter 111 is further configured to send a second message to the user equipment, where the second message is used to indicate that the user equipment acquires the data from the target base station.

Further, the first message may further include a radio bearer identifier, where the first message is used to indicate that the secondary base station switches the radio bearer to the target base station according to the radio bearer identifier.

As shown in FIG. 12, the base station 11 may further include:

The receiver 113 is configured to receive a data forwarding request message sent by the secondary base station, where the data forwarding request message is used to request data forwarding from the primary base station, where the data forwarding request message may include at least one of the following information: indicating that the primary base station performs Downlink forwarding information, the uplink general packet radio service tunneling protocol GTP endpoint information of the secondary base station for uplink data forwarding.

Further, the transmitter 111 may be further configured to send a data forwarding acknowledgement message to the secondary base station, where the data forwarding acknowledgement message includes GTP endpoint information of the primary base station.

The processor 112 may be further configured to determine that the secondary base station performs a partial radio access bearer handover, and the transmitter 111 may be further configured to send a radio access bearer handover message to the secondary base station, where the secondary base station performs the part of the radio access bearer. Switching to the target base station, the radio access bearer handover message includes the identifier of the part of the radio access 7 . Alternatively, the processor 112 may be further configured to determine that the secondary base station performs all radio access bearer handover, and the transmitter 111 may be further configured to send a secondary base station handover command to the secondary base station, where the secondary base station uses the secondary radio access bearer. Switch to the target base station.

It should be noted that, in any of the following cases, the transmitter 111 sends a first message to the secondary base station:

When the base station confirms that the signal quality of the secondary base station is lower than a preset threshold.

Or, when the base station receives the radio access bearer switching request sent by the secondary base station.

Or when the base station confirms that the wireless link connection between the user equipment and the secondary base station fails. By using the foregoing base station, seamless handover between base stations can be performed in the case of cell carrier aggregation between base stations, thereby avoiding data loss when handover occurs in the case of cell carrier aggregation between base stations, thereby realizing cell carrier aggregation between base stations. Accurate continuous transmission of data reduces the latency of data transmission.

The base station 13 provided by the embodiment of the present invention corresponds to the foregoing method embodiment, and is used as the secondary base station, and can be used in all the steps in the foregoing method embodiment. The detailed method steps corresponding to the base station 13 are described in the foregoing method embodiment, and are not described herein. More details will be described. As shown in FIG. 13, the method includes: a receiver 131, configured to receive a first message sent by a primary base station, where the first message is used to indicate that the base station performs handover, and the first message includes a target base station identifier.

The receiver 131 is further configured to receive a data forwarding acknowledgement message sent by the target base station, where the data forwarding acknowledgement message is used to confirm that the base station performs data forwarding to the target base station.

The transmitter 132 is configured to forward the second message to the primary base station, where the second message is used by the primary base station to instruct the user equipment to acquire the data from the target base station.

By using the foregoing base station, seamless handover between base stations can be performed in the case of cell carrier aggregation between base stations, thereby avoiding data loss when handover occurs in the case of cell carrier aggregation between base stations, thereby realizing cell carrier aggregation between base stations. Accurate continuous transmission of data reduces the latency of data transmission.

Further, as shown in FIG. 14, the base station 13 may further include: The processor 1 33 is configured to stop transmission of uplink and downlink data.

The transmitter 1 32 may be further configured to send a data forwarding request message to the target base station, where the data forwarding request message is used to request data forwarding from the target base station, where the data forwarding request message may include at least one of the following information: indicating the target base station Perform downlink forwarding information, the base station's uplink general packet radio service tunneling protocol GTP endpoint information for uplink data forwarding.

The data forwarding acknowledgement message may include GTP endpoint information of the target base station.

Further, when the primary base station determines that the base station performs partial radio access bearer handover, the receiver 1 31 may be further configured to receive the radio access bearer handover message sent by the primary base station, and the processor 1 33 may also be used to connect part of the radio access. The ingress bearer is switched to the target base station, and the radio access bearer switching message may include the identifier of the part of the radio access 7 .

Alternatively, when the primary base station determines that the base station performs all radio access bearer handover, the receiver 1 31 may also be configured to receive the secondary base station handover command sent by the primary base station, and the processor 1 33 may also be used to switch all radio access bearers. To the target base station.

It should be noted that the primary base station and the target base station may be the same base station.

The base station 15 provided by the embodiment of the present invention corresponds to the foregoing method embodiment, and is used as the target base station, and can be used in all the steps in the foregoing method embodiment. The detailed method steps corresponding to the base station 15 have been described in the foregoing method embodiment. More details will be described. As shown in FIG. 15, the SN information receiving unit 151 is configured to receive SN state transition information sent by the secondary base station. The handover request sending unit 152 is configured to send a path switching request to the mobility management entity. The handover confirmation receiving unit 153 is configured to receive the path switch confirmation information sent by the MME, and complete data forwarding.

Using the above base station, the base station can be aggregated without inter-base station cell carrier aggregation. The slot switching avoids data loss when handover occurs in the case of cell carrier aggregation between base stations, thereby realizing accurate and continuous data transmission during cell carrier aggregation between base stations, and reducing the delay of data transmission.

The user equipment 16 provided by the embodiment of the present invention is corresponding to the foregoing method embodiment, and may be used in all the steps in the foregoing method embodiment. The detailed method steps corresponding to the user equipment 16 are described in the foregoing method embodiment, and are not detailed here. description. As shown in Figure 16, it includes:

The receiving unit 161 is configured to receive a second message sent by the primary base station, where the second message is used to indicate that the user equipment acquires data from the target base station.

The protocol entity establishing unit 162 is configured to establish a target base station protocol entity according to the second message.

The forwarding unit 163 is configured to forward the cached data in the secondary base station protocol entity to the target base station protocol entity.

By using the foregoing user equipment, seamless handover between base stations can be performed in the case of inter-base station cell carrier aggregation, which avoids data loss when handover occurs in the case of inter-base station cell carrier aggregation, thereby implementing inter-base station cell carrier aggregation. Accurate continuous transmission of data reduces the delay of data transmission.

Embodiments of the present invention also provide a communication system including a primary base station and a secondary base station as described above.

The communication system provided by the embodiment of the present invention may further include at least one user equipment. The structure of the base station and the user equipment has been described in detail in the foregoing embodiments, and details are not described herein.

By using the above data forwarding system, seamless handover between base stations can be performed in the case of inter-base station cell carrier aggregation, which avoids data loss when handover occurs in the case of cell carrier aggregation between base stations, thereby realizing inter-base station cell carrier. Accurate continuous transmission of data during aggregation reduces the delay of data transmission.

One of ordinary skill in the art can understand that all or part of the steps of the above method embodiments are implemented. The foregoing may be performed by a program instruction related hardware, where the foregoing program may be stored in a computer readable storage medium, and when executed, the program includes the steps of the foregoing method embodiment; and the foregoing storage medium includes: R0M, A variety of media that can store program code, such as RAM, disk, or optical disk.

The above is only the specific embodiment of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art can easily think of changes or substitutions within the technical scope of the present invention. It should be covered by the scope of the present invention. Therefore, the scope of the invention should be determined by the scope of the appended claims.

Claims

Rights request

1. A data forwarding method, characterized by including:

The primary base station sends a first message to the secondary base station, the first message is used to instruct the secondary base station to perform handover, and the first message includes the target base station identifier;

The main base station confirms that the secondary base station forwards the data to the target base station; and the main base station sends a second message to the user equipment, the second message is used to instruct the user equipment to obtain the data from the target base station. data.

2. The method according to claim 1, characterized in that the primary base station sends a first message to the secondary base station, and the first message is used to instruct the secondary base station to perform handover, including:

The first message also includes a radio bearer identification, and the first message is used to instruct the secondary base station to switch a radio bearer to the target base station according to the radio bearer identification.

3. The method according to claim 1 or 2, characterized in that the method further includes:

The primary base station receives a data forwarding request message sent by the secondary base station. The data forwarding request message is used to request data forwarding to the primary base station. The data forwarding request message includes at least one of the following information: indicating that the The information of the primary base station for forwarding downlink data, and the uplink General Packet Radio Service Tunneling Protocol GTP endpoint information of the secondary base station for forwarding of uplink data;

The primary base station sends a data forwarding confirmation message to the secondary base station, where the data forwarding confirmation message includes GTP endpoint information of the primary base station.

4. The method according to claim 1, characterized in that the primary base station sends a first message to the secondary base station, including:

The primary base station determines that the secondary base station performs partial radio access bearer switching, and sends a radio access bearer switching message to the secondary base station for the secondary base station to switch the partial wireless access bearer. The wireless access bearer is switched to the target base station, and the wireless access bearer switching message includes the identification of the partial wireless access bearer; or

The primary base station determines that the secondary base station performs all wireless access bearer switching, and sends a secondary base station switching command to the secondary base station, for the secondary base station to switch all wireless access bearers to the target base station.

5. The method according to any one of claims 1 to 4, characterized in that, in any of the following situations, the primary base station sends the first message to the secondary base station:

When the primary base station confirms that the signal quality of the secondary base station is lower than the preset threshold; or,

When the primary base station receives the radio access bearer switching request sent by the secondary base station; or,

When the primary base station confirms that the wireless link connection between the user equipment and the secondary base station fails.

6. The method according to any one of claims 1 to 5, characterized in that the target base station is the main base station.

7. A data forwarding method, characterized by including:

The secondary base station receives the first message sent by the primary base station, the first message is used to instruct the secondary base station to perform handover, and the first message includes the target base station identifier;

The secondary base station receives a data forwarding confirmation message sent by the target base station, and the data forwarding confirmation message is used to confirm that the secondary base station forwards data to the target base station; the secondary base station sends a second step to the main base station. message, the second message is used by the main base station to instruct the user equipment to obtain the data from the target base station.

8. The method according to claim 7, characterized in that the secondary base station receives a first message sent by the primary base station, and the first message is used to instruct the secondary base station to perform handover, including:

The first message also includes a radio bearer identification, and the first message is used to indicate that the The secondary base station switches the radio bearer to the target base station according to the radio bearer identification.

9. The method according to claim 7 or 8, characterized in that, after the secondary base station receives the first message sent by the primary base station, the method further includes:

The secondary base station stops the transmission of uplink and downlink data.

10. The method according to any one of claims 7 to 9, characterized in that the method further includes:

The secondary base station sends a data forwarding request message to the target base station. The data forwarding request message is used to request data forwarding to the target base station. The data forwarding request message includes at least one of the following information: indicating that the Information for downlink forwarding by the target base station, and uplink General Packet Radio Service Tunneling Protocol GTP endpoint information of the secondary base station for uplink data forwarding;

The data forwarding confirmation message includes GTP endpoint information of the target base station.

11. The method according to claim 7, wherein the secondary base station receives the first message sent by the primary base station, including:

When the primary base station determines that the secondary base station performs partial radio access bearer switching, the secondary base station receives the radio access bearer switching message sent by the primary base station, and the secondary base station switches the partial radio access bearer. To the target base station, the radio access bearer switching message includes the identification of the partial radio access bearer; or

When the primary base station determines that the secondary base station performs all wireless access bearer switching, the secondary base station receives the secondary base station switching command sent by the primary base station, and the secondary base station switches all wireless access bearers to the secondary base station. Describe the target base station.

12. A base station, characterized by including:

A transmitter, configured to send a first message to the secondary base station, where the first message is used to instruct the secondary base station to perform handover, where the first message includes a target base station identifier;

a processor, configured to confirm that the secondary base station forwards data to the target base station; and the transmitter is further configured to send a second message to the user equipment, the second message is used to Instruct the user equipment to obtain the data from the target base station.

13. The base station according to claim 12, characterized in that:

14. The base station according to claim 12 or 13, characterized in that, the base station further includes:

A receiver, configured to receive a data forwarding request message sent by the secondary base station, where the data forwarding request message is used to request data forwarding to the base station, where the data forwarding request message includes at least one of the following information: indicating that the The downlink forwarding information of the base station, and the uplink General Packet Radio Service Tunneling Protocol GTP endpoint information of the secondary base station for uplink data forwarding;

The transmitter is also configured to send a data forwarding confirmation message to the secondary base station, where the data forwarding confirmation message includes GTP endpoint information of the base station.

15. The base station according to claim 12, characterized in that:

The processor is further configured to determine that the secondary base station performs partial radio access bearer switching, and the transmitter is further configured to send a radio access bearer switching message to the secondary base station, for the secondary base station to transfer the Part of the radio access bearers is switched to the target base station, and the radio access bearer switching message includes the identifier of the part of the radio access bearers; or

The processor is further configured to determine that the secondary base station performs all wireless access bearer switching, and the transmitter is further configured to send a secondary base station switching command to the secondary base station for the secondary base station to switch all wireless access bearers. The access bearer is switched to the target base station.

16. The base station according to any one of claims 12 to 15, characterized in that, in any of the following situations, the transmitter sends the first message to the secondary base station:

When the base station confirms that the signal quality of the secondary base station is lower than the preset threshold; when the base station receives the radio access bearer switching request sent by the secondary base station; when the base station confirms that the user equipment is connected to The wireless link connection of the secondary base station is lost. When defeated.

17. A base station, characterized by including:

A receiver, configured to receive a first message sent by the master base station, where the first message is used to instruct the base station to switch, where the first message includes a target base station identifier;

The receiver is further configured to receive a data forwarding confirmation message sent by the target base station, where the data forwarding confirmation message is used to confirm that the base station forwards data to the target base station;

A transmitter, configured to forward a second message to the main base station, where the second message is used by the main base station to instruct the user equipment to obtain the data from the target base station.

18. The base station according to claim 17, characterized in that:

The first message also includes a radio bearer identification, and the first message is used to instruct the base station to switch a radio bearer to the target base station according to the radio bearer identification.

19. The base station according to claim 17 or 18, characterized in that, the base station further includes:

Processor, used to stop the transmission of upstream and downstream data.

20. The base station according to any one of claims 17 to 19, characterized in that: the transmitter is also used to send a data forwarding request message to the target base station, and the data forwarding request message is used to send the data to the target base station. The base station requests data forwarding, and the data forwarding request message includes at least one of the following information: information instructing the target base station to perform downlink forwarding, and uplink General Packet Radio Service Tunneling Protocol GTP endpoint information of the base station for uplink data forwarding. ;

21. The base station according to claim 17, characterized in that:

When the main base station determines that the base station performs partial radio access bearer switching, the receiver is also used to receive the radio access bearer switching message sent by the main base station, and the processor is also used to convert the partial radio access bearer switching. The wireless access bearer is switched to the target base station, and the wireless The access bearer switching message includes the identification of the part of the radio access bearer; or

When the main base station determines that the base station performs all wireless access bearer switching, the receiver is also used to receive a secondary base station switching command sent by the main base station, and the processor is also used to switch all wireless access bearers. The incoming bearer is switched to the target base station.

22. A communication system, characterized in that it includes: the base station according to any one of claims 12 to 16 and the base station according to any one of claims 17 to 21.